JP2002286609A - Method and program for controlling moisture meter, recording medium recording the program, and moisture meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and program for controlling moisture meter and a recording medium recording the program and a moisture meter by which the measurement condition of a moisture meter, particularly, a heating and drying type moisture meter can be set easily and surely. SOLUTION: The parameter of a time function indicating the variation of the moisture percent of the moisture meter is detected by successively raising the heating temperature of the meter in steps and, at the same time, the optimum heating temperature of the meter is calculated based on the parameter. In addition, the required mass of a sample is calculated from the measurement accuracy set by means of the operator of the meter and the measurement accuracy of the mass.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a moisture meter, a control program for a moisture meter, a recording medium on which a control program for a moisture meter is recorded, and a moisture meter, and particularly to a heat-drying moisture meter. it can. The present invention increases the heating temperature in a stepwise manner, detects a parameter of a time function indicating a change in moisture percentage, and calculates an optimal heating temperature based on the parameter, or is set by an operator. By calculating the required mass of the sample from the measured accuracy and the measured accuracy of the mass, it is possible to easily and reliably set the measurement conditions.

[0002]

2. Description of the Related Art Conventionally, in a heat-drying type moisture meter,
The water content of a sample is detected by measuring the change in mass by evaporating water by heating.
That is, the mass of the sample before starting such heating (hereinafter referred to as the mass before drying) is W, and the mass of the sample after drying is D.
In other words, the water content WP of the sample can be expressed by the following equation.

[0003]

(Equation 1)

As a result, in a heat-drying type moisture meter, as the amount of the sample is increased, the measurement accuracy is correspondingly improved, but the time required for drying is longer, and the measurement time is longer. For this reason, in the conventional moisture meter, the required accuracy is X [%], and the weight measurement accuracy in the moisture meter is M
In [g], the calculation of N = M / X is executed by the operator to obtain the mass N of the sample. By this, the measurement accuracy of the weight is 1 [mg],
When calculating the water content with an accuracy of 0.01 [%], the amount of the sample is 10 [g].

In a heat-drying type moisture meter, when the heating temperature is increased, moisture can be evaporated in a short time, so that the time required for measurement can be shortened. However, when the heating temperature is increased, liquids other than water contained in the sample (for example, volatile oil components) are volatilized and decomposed, and when the temperature is further increased, the organic substances contained in the sample are carbonized, thereby deteriorating the measurement accuracy. Will do.

[0006] Thus, in the conventional moisture meter, the heating conditions are set by preliminary preliminary experiments. Here, the heating conditions include a time for drying the sample by heating (heating time), a heating temperature, a time from when heating is started to when the temperature is raised to the heating temperature (heating time).

That is, in this preliminary test, the sample is heated for a predetermined time at a constant temperature, and it is detected whether or not the mass of the sample does not change due to evaporation of water. The heating in such a preliminary test is performed at a temperature of, for example, 120 degrees for 10 minutes. When the mass of the sample continues to change even with such constant temperature and constant time heating,
The heating temperature is changed or extended by the heating temperature until the mass of the sample no longer changes.

In the preliminary test, a plurality of samples are prepared,
The sample is dried by variously changing the heating temperature, the heating time, and the heating time, and the heating conditions determined to be appropriate are set based on the test results.

That is, in the measurement of the moisture content by a conventional moisture meter, the heating conditions obtained in this way are set in the moisture meter, and then a sample of a calculated amount is placed.
Thereafter, when the measurement is started, the moisture meter detects and records the mass of the sample before drying, and starts heating the sample under the conditions set by the user. After that, the mass during drying is monitored, and based on the monitored result, the measurement result of the moisture content is displayed by the arithmetic processing of the equation (1). When the heating time elapses, the heating is stopped and the measurement result is displayed. It has been done.

[0010]

However, in such a manner, in determining the heating conditions by the preliminary test, there is a problem that the conditions cannot be easily and reliably determined.

That is, as described above, in the preliminary test, it is necessary to prepare a plurality of samples and repeat heating, so that there is a problem that a long time is required for measurement.

In some cases, the volatile components evaporate and the mass of the sample does not change. In such a case, the heating condition is determined by erroneously determining that the mass of the sample does not change due to evaporation of water. There is a possibility that the conditions may be set, and it is conceivable that the conditions thus set are not appropriate. By the way, by this, in the conventional heating and drying meter,
Skill was required to determine the heating conditions.

In this connection, since it takes a long time to measure each of the plurality of samples, the evaporation of the moisture is prevented in each of the plurality of samples until the measurement is started. It is necessary to keep the water content unchanged, and maintenance and management of such water content requires a large amount of maintenance of the measurement environment. In addition, the preliminary test becomes complicated, and this complicated work is one factor of erroneous measurement of the moisture content.

The present invention has been made in consideration of the above points, and has a moisture meter capable of easily and reliably setting measurement conditions, a moisture meter control method, a moisture meter control program, and a moisture meter control program. It is intended to propose a recording medium on which a control program is recorded.

[0015]

In order to solve the above-mentioned problems, the invention according to claim 1 is applied to a control method of a moisture meter, and the heating temperature is sequentially increased step by step to prepare a sample for a preliminary test. A step of detecting a change in the moisture percentage by heating to detect a change in the moisture percentage; and a step of detecting a parameter of a time function indicating the change in the moisture percentage based on the change in the moisture percentage detected in the step of detecting the moisture percentage. And a step of selecting a temperature suitable for heating the sample based on the parameters.

In the invention of claim 2, claim 1
In the configuration of (1), the temperature selecting step selects a temperature suitable for heating based on a change in a parameter between heating temperatures that gradually increase in stages.

Further, in the invention of claim 3, claim 1
Alternatively, in the configuration according to claim 2, the step of selecting the temperature includes:
Using the parameter detected by the heating temperature up to immediately before, the parameter detected at the subsequent heating temperature is calculated, and the calculated parameter is compared with the parameter based on the actually measured value, so that the immediately preceding heating temperature is suitable for heating. Choose the temperature.

According to a fourth aspect of the present invention, in the configuration of the first, second, or third aspect, a heating time calculation for calculating a time required for heating using a parameter based on a temperature suitable for heating. Have a step.

According to the fifth aspect of the present invention, there is provided a fourth aspect.
In the heating time calculation step, the time required for heating is calculated by calculating a time function based on parameters based on the measurement accuracy set by the operator.

In the invention of claim 6, in the configuration of claim 1, claim 2, claim 3, claim 4, or claim 5, the time function is a natural logarithmic function.

According to the seventh aspect of the present invention, a mass calculation method for calculating a required sample mass from the measurement accuracy set by an operator and the measurement accuracy of the sample mass by applying to the control method of the moisture meter. To have the following steps.

In the invention of claim 8, in the structure of claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, or claim 7, the operator is notified of the processing result. It has a notification step.

[0023] In the ninth aspect of the present invention, the present invention is applied to a control program for a moisture meter, and is applied to the first, second, third, fourth, fifth, sixth, seventh, or seventh aspect. A control program according to the control method for a moisture meter according to claim 8 is provided.

According to a tenth aspect of the present invention, the control program according to the ninth aspect is applied to a recording medium on which the control program is recorded.

In the eleventh aspect, the present invention is applied to a moisture meter, and the moisture according to the first, second, third, fourth, fifth, sixth or seventh aspect is applied. The conditions for the measurement are calculated by the control method of the meter.

According to the twelfth aspect of the present invention, in the configuration of the eleventh aspect, a notifying means for notifying an operator of a processing result is provided.

According to the first aspect of the present invention, the heating temperature is sequentially increased stepwise, the sample for the preliminary test is heated to detect a change in the moisture content, and a moisture content detection step is performed. A step of detecting a parameter of a time function indicating a change in the moisture percentage based on the change in the moisture percentage detected in the step; and a step of selecting a temperature suitable for heating the sample based on the parameter. By having the above, it is possible to detect whether or not the heating state has shifted from the moisture evaporation stage to the next stage by judging the parameter, whereby the heating temperature can be appropriately adjusted by using one preliminary test sample. And in a short time. Measurement conditions can be set easily and reliably.

According to a second aspect of the present invention, in the first aspect, the step of selecting a temperature selects a temperature suitable for heating based on a change in a parameter between heating temperatures that gradually increase in steps. This makes it possible to easily and reliably detect whether or not the heating stage has shifted from the moisture evaporation stage to the next stage.

According to a third aspect of the present invention, in the first or second aspect, the step of selecting a temperature is detected at a subsequent heating temperature by using a parameter detected by the immediately preceding heating temperature. By comparing the calculated parameters with the parameters based on the actually measured values, by selecting the immediately preceding heating temperature to a temperature suitable for heating, the heating stage is changed from the moisture evaporation stage to the next stage. The heating temperature can be set to the temperature immediately before shifting to.

Further, according to the configuration of claim 4, claim 1,
In the configuration of claim 2 or claim 3, by having a heating time calculating step of calculating a time required for heating by using a parameter based on a temperature suitable for heating, the parameter used for determining the condition of the heating temperature can be obtained. The heating time can be determined effectively, and the measurement conditions can be set more easily and reliably.

According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the step of calculating the heating time is performed by calculating a time function based on a parameter based on the measurement accuracy set by the operator. By calculating the time required for the heating, a heating time sufficient to satisfy the measurement accuracy can be obtained.

Further, according to the configuration of claim 6, claim 1,
In the configuration of claim 2, claim 3, claim 4, or claim 5, since the time function is a natural logarithmic function, the change in the moisture content due to heating is approximated with sufficient accuracy, and the heating temperature and the heating time are calculated. And so on.

According to the seventh aspect of the present invention, there is provided a mass calculation step for calculating the required mass of the sample from the measurement accuracy set by the operator and the measurement accuracy of the mass of the sample. It is possible to simply and reliably detect the mass of a sample that can be measured in a short time, which is sufficient to satisfy the accuracy, and thus the measurement conditions can be set simply and reliably.

According to the configuration of claim 8, claim 1, claim 1,
In the configuration of claim 2, claim 3, claim 4, claim 5, claim 6, or claim 7, a step of notifying the processing result to the operator is provided, whereby the measurement of the measurement selected in this manner is performed. The condition can be notified to the operator to assist the operator in setting the measurement condition.

According to the ninth aspect of the present invention, it is possible to provide a control program for a moisture meter that can easily and surely set measurement conditions.

According to the tenth aspect of the present invention, it is possible to provide a recording medium in which a control program for a moisture meter, which can easily and surely set measurement conditions, is recorded.

According to the eleventh or twelfth aspect of the present invention, it is possible to provide a moisture meter capable of easily and surely setting measurement conditions.

[0038]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(1) Configuration of Embodiment FIG. 2 is a block diagram showing a moisture meter according to an embodiment of the present invention. In the moisture meter 1, the sample dish 2 is detachably held so that a sample can be placed thereon. The load sensor 3 outputs a load detection signal whose signal level changes according to the load on the sample dish 2. The analog-to-digital converter (A / D) 4 performs analog-to-digital conversion processing on the load detection signal and outputs load detection data to the arithmetic processing unit 5. Thereby, the arithmetic processing unit 5 sets the sample dish 2
The mass of the sample placed in the sample, and a change in the mass can be detected.

The halogen lamp 6 is a heat source for heating the sample, and is driven by the temperature controller 7 to emit light for heating the sample. The temperature sensor 8 is disposed near the sample dish 2 and outputs a temperature detection signal whose signal level changes according to the temperature. The temperature control unit 7 controls the temperature of the sample by the arithmetic processing unit 5.
The heating lamp 6 is driven while monitoring the heating result by the temperature detection signal so that the temperature is instructed by.

The display unit 10 is formed by a liquid crystal display panel or the like, and displays various settings by a user, measurement results, and the like. The interface 11 outputs a measurement result or the like to an external device such as a personal computer under the control of the arithmetic processing unit 5, and outputs data of various settings by the external device to the arithmetic processing unit 5. The timer 12 counts the current time and outputs the count result to the arithmetic processing unit 5. The memory 13 forms a work area of the arithmetic processing unit 5 and records measurement results and the like. The key switch unit 14 is configured by pressing operators and the like necessary for operation of the moisture meter 1, and performs various operations by the user on the arithmetic processing unit 5.
Notify.

The arithmetic processing unit 5 is a computer for controlling the operation of the entire moisture meter 1, and performs preliminary experiments, actual measurements, and the like by user operation notified from the key switch unit 14 and further by control of external devices. Execute the processing of

The arithmetic processing section 5 executes the processing procedure shown in FIG. 1 in the processing of this preliminary experiment, thereby instructing the user on the heating conditions and the weight of the sample to be used for the actual measurement. That is, when the user instructs the start of the preliminary experiment, the arithmetic processing unit 5 proceeds from step SP1 to step SP1.
2 and display the settable measurement accuracy on the display unit 10;
By detecting an operation of the key switch unit 14 corresponding to this display, an input of measurement accuracy is accepted.

Subsequently, the operation processing section 5 proceeds to step SP3, and executes an operation process conventionally calculated by the operator based on the load measurement accuracy of the moisture meter and the measurement accuracy of the moisture content input by the user. Thus, the required mass of the sample is calculated and displayed on the display unit 10. Thereby, the arithmetic processing unit 5 notifies the operator of the required mass of the sample.

Subsequently, the processing unit 5 proceeds to step SP4, and under the control of the temperature control unit 7, the reference temperature h0 on the low temperature side.
The heating of the sample is started by a degree (for example, 100 degrees). Further, the arithmetic processing unit 5 stores the heating start time,
Moving to step SP4, heating is started, and a predetermined time elapses, and the moisture content is measured. Here, this measurement is performed at least three times at different times after a lapse of time sufficient for starting the heating and increasing the temperature of the sample, and the moisture content is calculated at each measurement time.

When the moisture content is measured in this manner, the arithmetic processing unit 5 calculates the parameter p0 of the moisture content change curve by using the results of the moisture content measured by these three measurements. That is, the moisture percentage WP after elapse of t seconds from the start of heating
(T) is represented by the following time function.

[0047]

(Equation 2)

Here, when heating at a constant temperature, the change in the moisture content can be modeled by a natural logarithmic curve as shown in FIG. 3, and the moisture content WP (t) is expressed by the following general formula: Can be represented by

[0049]

(Equation 3)

Here, WP is the moisture content after drying, and K
(T) is a parameter of the moisture content change curve which is a time function. In the natural logarithmic curve, it can be represented by the following polynomial using the elapsed time t (second) after the start of heating. Note that An to A1 are constants.

[0051]

(Equation 4)

This polynomial can usually be approximated with sufficient accuracy by a linear equation represented by the following equation.

[0053]

(Equation 5)

In the natural logarithmic curve expressed by using the heating time as a variable, substances other than moisture evaporate,
Assuming that it does not decompose, the heating temperature can be expressed as a variable. Accordingly, if the condition of the heating temperature is added to the equation (4), the equation (4) can be expressed by the following equation. H is the heating temperature, and Bn to B0 are
Is a constant.

[0055]

(Equation 6)

Here, each series constituting the right side of the equation (6) can be approximated by a linear equation.
The equation can be represented by the following equation. C1 and C0 are constants.

[0057]

(Equation 7)

In summary, equation (3) can be expressed by the following equation.

[0059]

(Equation 8)

The arithmetic processing unit 5 calculates the variable p represented by the equation (8) by the processing in step SP5. Further, the arithmetic processing unit 5 records the calculation result in the memory 13 together with the heating temperature. The operation processing unit 5
In this case, the timing of the measurement of the moisture content in step SP5 is set so that the variation of the moisture content can be approximated with sufficient accuracy when the variation of the moisture content is approximated by a natural logarithmic curve.

Specifically, by differentiating both sides of equation (8) with time t, the following equation can be obtained.

[0062]

(Equation 9)

By rearranging equation (9), the following equation can be obtained.

[0064]

(Equation 10)

By substituting this equation into equation (8), the following equation can be obtained.

[0066]

[Equation 11]

By further rearranging the equation (11), the following relational equation can be obtained.

[0068]

(Equation 12)

Here, the equation (12) indicates that the moisture content after drying W
Since P and the parameter p are unknown, the parameter p can be calculated by solving the simultaneous equation of the equation (12) using the measurement results of the moisture content at least three times. As a result, the arithmetic processing unit 5 determines in step S
In the process at P5, the parameter p is calculated by solving the equation (12) for the parameter p using the moisture percentage WP (t) obtained by three moisture percentage measurements.

That is, for example, when a change in the moisture content as shown in FIG. 4 is observed, four minutes after the start of heating,
After 4 minutes, 30 seconds, and 5 minutes, the moisture percentages were calculated, and these moisture percentages were 7.02 [%] and 7.70, respectively.
[%] And 8.35 [%], a simultaneous equation represented by the following equation can be obtained.

[0071]

(Equation 13)

Thus, in this case, by solving this relational expression, the parameter p can be obtained by p0 = −1.849 × 10 ⁻³ .

When the parameter p0 is obtained from the initial heating temperature h0 in this way, the processing unit 5 proceeds to step SP6, where the heating temperature is increased by a predetermined temperature and the heating temperature h1 (for example, 120 ° C.) To start heating the sample. In the following step SP7, the parameter p1 is calculated in the same manner as in step SP5.

Subsequently, the operation processing section 5 proceeds to step SP8, where the two parameters p0 calculated in this manner are calculated.
And p1 are used to calculate constants C1 and C0 in equation (8).
Here, in this calculation, it can be obtained by solving two simultaneous equations using the parameters p0 and p1. That is, as shown in FIG. 4, the heating was started at the subsequent heating temperature h1, and after 6 minutes, 6 minutes, 30 seconds, and 7 minutes from the initial heating start point, the water contents were calculated, and these water contents were calculated. Are 10.26 [%], 1
When 1.10% and 11.87%, (1
A simultaneous equation similar to the equation 3) can be obtained, and p1 = −3.139 × 10 ⁻³ can be obtained by solving the simultaneous equation.

As a result, p0 = −1.849 × 10 ⁻³ ,
Substituting p1 = −3.139 × 10 ⁻³ into the equation (8),
The following simultaneous equations can be obtained.

[0076]

[Equation 14]

By solving this simultaneous equation, C1
= -64.5 × 10 ^-6 and C0 = 4.6 × 10 ^-3 can be obtained. After calculating the constants C1 and C0 in this way, the processing unit 5 proceeds to step SP9 (FIG. 5), where the temperature is further increased by a predetermined temperature and the heating temperature is set to hn.

Further, the arithmetic processing section 5 executes step SP10
And the parameter pn is calculated in the same manner as in step SP5.

Subsequently, the arithmetic processing unit 5 proceeds to step SP11
Then, from the constants C1 and C0 calculated in step SP8, the parameter px at the heating temperature hn is calculated using the equation (8). Further, the arithmetic processing unit 5 proceeds to step SP12, and determines whether or not the parameter px calculated in step SP11 and the parameter pn calculated from the moisture content in step SP10 substantially match.
By this determination, the arithmetic processing unit 5 determines whether or not the heating stage has shifted from the moisture drying stage to the next stage.

That is, in the test object subjected to this type of test, when the heating temperature is low, components such as alcohol which evaporate at a lower temperature than water (low volatile components) evaporate, and then the heating temperature is increased. , The water evaporates. When the heating temperature is further increased, the additives of the resin and the oil components of the sample (which are highly volatile components) evaporate, and when the temperature is further increased, decomposition and dissolution of organic substances occur, and furthermore, the organic components are removed. Start carbonization.

Thus, the change in the mass of this type of sample can be discriminated from the stage due to the evaporation of moisture and the stage other than the evaporation of the moisture based on the heating temperature, and the moisture content can be correctly measured by the moisture meter. In this case, it is necessary to measure while maintaining the heating temperature at the stage due to the evaporation of water. In addition, in order to shorten the measurement time, it is necessary to heat at a heating temperature set at the heating temperature of the stage due to evaporation of moisture and as high as possible.

When the change in the moisture content is expressed by the time function as described above, the parameters C1 and C0 of the time function detected from the measurement result of the moisture content in the evaporation stage of the moisture will cause each heating. The temperature will be almost the same. On the other hand, when the heating stage shifts from the moisture evaporation stage to another stage, for example, by evaporating to oil and the like other than moisture, the measurement result of the change in the moisture content can be expressed by a time function in the moisture evaporation stage. Disappears. That is, in this case, as described above, the constants C1 and C0 representing the measurement result by the time function exhibit different values from the constants at the previous stage.

Thus, in this embodiment, in this step SP12, the parameter Px predicted by the constants C1 and C0 detected in the previous measurement is compared with the actually measured parameter Pn, and the next heating stage is performed. It is determined whether or not the process has shifted to the stage.

In step SP12, if a comparison result indicating that these two types of parameters Px and Pn are substantially the same is obtained, in this case, there is still room for raising the heating temperature in the stage of evaporation of moisture. In some cases, the arithmetic processing unit 5
Moving to step SP9, the temperature is further increased.

Thus, the arithmetic processing unit 5 repeats the processing procedure of steps SP9-SP10-SP11-SP12-SP9 until the heating step shifts from the moisture evaporation step to the next step, and sequentially increases the heating temperature. Let it.

FIG. 6 is a table showing actual measurement results when the temperature is increased in this manner. In this case, when the heating temperature is set to 180 degrees, the two types of parameters Px and Pn have clearly different values, which indicates that the heating temperature has shifted to the next stage.

When the stage of heating shifts from the stage of evaporation of water to the next stage, a negative result is obtained in step SP12, so that the arithmetic processing unit 5 executes step SP
The process moves from step 12 to step SP13. Here, in this case, the current heating state is shifted to the next stage from the moisture evaporation stage, and the immediately preceding heating state is determined to be the moisture evaporation stage. The processing unit 5 sets the immediately preceding heating temperature to the optimal heating temperature.

Subsequently, the arithmetic processing unit 5 proceeds to step SP14
To the parameter P detected at the optimal heating temperature.
By substituting n-1 into the equation (8), an optimum heating time is calculated so as to satisfy the required accuracy input in step SP2. That is, in the present embodiment, in the calculation using the equation (8), the time point at which the moisture content falls below the measurement accuracy specified by the user with respect to the final value of the moisture content is set as the end time of heating. That is, in this case, for example, when the operator indicates a measurement accuracy of 0.2 [%] as the required accuracy, the following expression can be obtained from Expression (8).

[0089]

(Equation 15)

(Equation 16)

[Equation 17]

Here, the power detected at the temperature of 160 ° C. in FIG.
Value of parameter p−5.862 × 10 ^-3Into equation (17)
In this case, the time required for heating t = 106
8 seconds ($ 18 minutes) can be calculated.

When the heating time is calculated in this way, the arithmetic processing unit 5 calculates the sample amount calculated in step SP3,
Heating temperature calculated in step SP14, step SP1
The heating time calculated in step 5 is displayed on the display unit 10 to notify the processing result to the operator. After that, the arithmetic processing unit 5 moves to step SP16 and ends this processing procedure.

In this case, the arithmetic processing unit 5 sets the test conditions by the operator when the operator instructs the start of the test based on the test conditions notified as described above or by referring to the test conditions notified as described above. Later, when the operator instructs the start of the test, the heating of the sample is started and the moisture content is monitored according to the test conditions instructed by the operator, and when the heating time is reached, the test is terminated.
Further, the operator is notified of the moisture content at the end of the process.

(2) Operation of Embodiment In the above configuration, in the moisture meter 1 (FIGS. 1 and 2), when the operator operates the key switch section 14 to input the required measurement accuracy, the load is Based on the measurement accuracy of the mass in the moisture meter 1 determined by the processing of the sensor 3, the analog-to-digital converter 4, and the arithmetic processing unit 5, the minimum sample mass necessary to secure the measurement accuracy is calculated. Calculated in part 5. Further, the calculation result is displayed on the display unit 10. As a result, the operator can start the preliminary test and the actual test simply by placing the sample amount displayed on the display unit 10 on the sample dish 2, and accordingly, one of the tests can be easily performed. The sample amount, which is a condition, can be set.

That is, such a moisture meter may be used, for example, for quality control. In this case, unless the moisture content is always measured with a fixed sample amount, the measurement time varies or the moisture content may be reduced. Errors may occur. In particular, such an error becomes remarkable when a change in the moisture content due to a fixed heating time is managed.

However, even if it is desirable to manage the sample with a fixed sample amount, it is practically necessary for the operator to secure the necessary measurement accuracy and determine the sample amount that can be measured in a short time. It was confusing. However, as in this embodiment,
By simply calculating the required measurement accuracy on the device side and notifying the operator of the required sample amount based on the input of the required measurement accuracy, such a complicated sample amount setting operation can be omitted. In addition, since this sample amount is a sample amount that can be measured in a short time while securing necessary measurement accuracy, a measurement result can always be obtained under optimal conditions. This makes it possible to easily and reliably set the measurement conditions for the sample amount.

In the preliminary test, after the sample is placed on the sample dish 2 according to the sample amount and the like notified in this way, when the user instructs to start the preliminary test, the moisture meter 1 Minimum temperature 1 sufficient for evaporation
Heating of the sample is started by 00 degrees (FIGS. 3 and 4),
Thereafter, every time a predetermined time elapses, the moisture content is measured.
In the moisture meter 1, when this measurement is repeated three times, the parameter p0 of the time function indicating the change in the moisture content is detected from the results of these three measurements.

Subsequently, the temperature is increased by a predetermined temperature, and similarly, the parameter p1 of the time function is detected. In the moisture meter 1, coefficients C0 and C1 of a temperature function for deriving the parameters p0 and p1 are calculated from the parameters p0 and p1 detected continuously.

Further, in the moisture meter 1, the heating temperature is raised again, and the parameter p2 based on the subsequent heating temperature is calculated by the same measurement of the moisture content. Further, a parameter px at the heating temperature is calculated using the coefficients C0 and C1 of the temperature function calculated in the immediately preceding calculation. By comparing the two parameters p2 and px, the heating is performed based on the change in the parameter. The state is determined. That is, in the stage where moisture is evaporated by heating, the parameter p2 actually measured in this way is a parameter px calculated by a temperature function using the coefficients C0 and C1.
However, when the heating state has shifted to a stage where the oil content evaporates or the like, it does not match.

Thus, when it is determined that the moisture has not yet moved to the next stage, the moisture meter 1 further raises the heating temperature and repeats the same processing procedure. If it can be determined that the process has shifted to the stage, the immediately preceding heating temperature is set to the optimal heating temperature. Thus, the heating temperature set in this manner is the temperature of the moisture evaporation stage, and the highest temperature in the moisture evaporation stage, so that the heating time is short and the moisture Is the heating temperature that can only evaporate. Thus, in this embodiment, the heating temperature, which is one of the measurement conditions, can be reliably detected in a short time.

In detecting the heating temperature in this way, in the moisture meter 1, a natural logarithmic curve is applied to the time function. In other words, in such evaporation of water, the change in the water content rapidly decreases at the start of heating, whereas the change in the water content gradually decreases with the decrease in the water content. The change in the water content can be approximated with high precision by the logarithmic curve. Thus, in this embodiment, the measurement conditions can be set with high accuracy.

When the heating temperature is calculated in this manner, in the moisture meter 1, the heating of the sample is stopped and the preliminary test is completed. At this time, the moisture meter 1 calculates the heating time required to secure the measurement accuracy specified by the operator, using the parameter p used for the calculation of the heating temperature. That is, even in such a calculation of the heating time, it has been conventionally difficult to calculate the heating time in order to enable the measurement in a short time under the condition of ensuring the measurement accuracy. However, in this embodiment, by taking into account such measurement accuracy and making effective use of the time function used in the calculation of the heating time, the calculation is performed simply and reliably under one of the measurement conditions. A certain heating time can be determined.

Thus, in the moisture meter 1, the sample amount, the heating temperature and the heating time calculated in this way are displayed on the display section 10, and the operator can start the measurement in accordance with the display, thereby easily and reliably. The moisture content can be measured.

(3) Effects of the Embodiment According to the above configuration, the heating temperature is increased stepwise in order to detect the parameter of the time function indicating the change in the moisture content, and to determine the optimal value based on this parameter. By calculating a proper heating temperature, measurement conditions can be set easily and reliably.

That is, by selecting a temperature suitable for heating based on such a change in the parameter of the time function, it is possible to easily and reliably discriminate the stage of moisture evaporation from the next stage. This makes it possible to easily detect the heating temperature at which the measurement can be completed in a short time.

At this time, the parameter detected at the subsequent heating temperature is calculated using the parameter detected at the immediately preceding heating temperature, and the calculated parameter is compared with the parameter based on the actually measured value to determine the immediately preceding heating temperature. By selecting a temperature suitable for heating, it is possible to select the highest heating temperature in the stage of evaporating the moisture, thereby completing the measurement easily and in a short time. Can be detected.

The heating time is calculated by using the temperature parameter suitable for heating obtained in this manner, so that the heating time among the measurement conditions can be set simply and reliably. be able to.

In this calculation of the heating time, the heating time is set so that the measurement accuracy desired by the user can be ensured by calculating the time function based on the parameters based on the measurement accuracy set by the operator. This also makes it possible to set measurement conditions simply and reliably.

Further, by applying the natural logarithmic function to the time function used for such calculation, it is possible to calculate the heating time and the like by accurately approximating the change in the water content. It can be set easily and reliably.

Further, by calculating the required mass of the sample from the measurement accuracy set by the operator and the measurement accuracy of the mass of the sample, it is possible to easily and surely determine the mass of the sample among the measurement conditions. The quantity can be set.

(4) Other Embodiments In the above embodiment, the parameter p calculated from the temperature function coefficients C0 and C1 representing the parameter p is used.
x, and the case where the transition of the heating stage is determined with high accuracy by comparing the parameter pn by the actual measurement has been described. However, the present invention is not limited to this, and when sufficient accuracy for practical use can be secured, For example, the heating temperature may be selected based on the change in the parameter pn, such as when the transition of the heating stage is determined simply by determining the magnitude of the change in the parameter pn with respect to the temperature. May be selected.

Further, in the above-described embodiment, the case where the change in the moisture content is expressed by a natural logarithmic function has been described. However, the present invention is not limited to this. Can be applied.

In the above-described embodiment, the final drying rate WP is reduced to the value corresponding to the measurement accuracy.
Although the case where the time point at which P (t) changes is set as the time point at which the heating is completed has been described, the present invention is not limited to this. For example, the case where the final drying rate WP is obtained by prediction may be considered. In such a case, the heating time can be set variously using various time functions using the parameter p.

In the above-described embodiment, a case has been described in which the result of the preliminary experiment is notified to the operator and the setting by the operator is accepted. However, the present invention is not limited to this. The actual measurement may be performed in an appropriate manner.

In the above-described embodiments, the case where a halogen lamp is used as a heating source has been described. However, the present invention is not limited to this, and can be widely applied to a case where various heaters and the like are used as a heating source. Can be.

In the above-described embodiment, the case where the present invention is applied to a moisture meter has been described. However, the present invention is not limited to this, and the present invention is also applicable to a case where the moisture meter is used by being controlled by a computer as an external device. As a result, it can be widely applied to such a case. In this case, the computer as the external device executes all or a part of the processing in the arithmetic processing unit according to the above-described embodiment.

[0116]

As described above, according to the present invention, the heating temperature is increased stepwise in order to detect a parameter of a time function indicating a change in the moisture content, and to determine an optimum heating temperature based on this parameter. , Or by calculating the required mass of the sample from the measurement accuracy set by the operator and the measurement accuracy of the mass, measurement conditions can be easily and reliably set.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a processing procedure of an arithmetic processing unit in a moisture meter according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a moisture meter by an arithmetic processing unit in FIG. 1;

FIG. 3 is a characteristic curve diagram showing a change in a moisture content according to each heating temperature.

FIG. 4 is a characteristic curve diagram showing a change in moisture content when the heating temperature is increased stepwise.

FIG. 5 is a flowchart showing a continuation of FIG. 1;

FIG. 6 is a table showing measurement results and calculated parameters p in comparison with FIG. 4;

[Explanation of symbols]

1 ... Moisture meter, 2 ... Sample dish, 3 ... Load sensor, 5 ...
… Arithmetic processing unit, 6… halogen lamp

Claims (12)

[Claims] 1. A method for controlling a moisture meter for measuring a moisture content of a sample based on a change in mass detected by heating the sample by a heat source, wherein the heating temperature is increased stepwise in order to prepare a sample for a preliminary test. A step of detecting a change in the moisture percentage by heating the sample, and a parameter detection for detecting a parameter of a time function indicating the change in the moisture percentage based on the change in the moisture percentage detected in the step of detecting the moisture percentage. And a temperature selecting step of selecting a temperature suitable for heating the sample based on the parameter. 2. The method according to claim 1, wherein the step of selecting a temperature selects a temperature suitable for the heating based on a change in the parameter between the heating temperatures that are gradually increased. How to control the moisture meter. 3. The step of selecting a temperature includes calculating a parameter detected at a subsequent heating temperature by using a parameter detected by a heating temperature immediately before, and calculating a parameter obtained by the calculated parameter and a parameter based on an actually measured value. The method according to claim 1 or 2, wherein the immediately preceding heating temperature is selected to be a temperature suitable for the heating by comparison. 4. The method according to claim 1, further comprising a heating time calculating step of calculating a time required for heating using the parameter according to a temperature suitable for the heating. The control method of the described moisture meter. 5. The heating time calculation step is characterized in that the time required for the heating is calculated by calculating the time function based on the parameter based on a measurement accuracy set by an operator. A method for controlling a moisture meter according to claim 4. 6. The control method for a moisture meter according to claim 1, wherein the time function is a natural logarithmic function. 7. A method for controlling a moisture meter for measuring a moisture content of a sample based on a change in mass detected by heating the sample by a heat source, wherein a measurement accuracy set by an operator and a measurement accuracy of the mass of the sample are measured. And a mass calculating step of calculating a required mass of the sample from the above. 8. The method according to claim 1, further comprising the step of notifying an operator of a processing result.
Claim 3, Claim 4, Claim 5, Claim 6, or Claim 7
The method for controlling a moisture meter according to item 1. 9. A control program according to the method for controlling a moisture meter according to claim 1, claim 2, claim 3, claim 3, claim 4, claim 5, claim 6, claim 7, or claim 8. A control program for a moisture meter characterized by the following. 10. A recording medium on which a control program for a moisture meter, wherein the control program for a moisture meter according to claim 9 is recorded. 11. The method for controlling a moisture meter according to claim 1, claim 2, claim 3, claim 4, claim 5, claim 6, or claim 7, wherein a condition to be used for measurement is calculated. A moisture meter characterized by the following. 12. The moisture meter according to claim 11, further comprising notification means for notifying an operator of a processing result.